U.S. Pat. No. 6,892,091 B1 discloses an apparatus and a method for generating an electrical map of a chamber of a heart, wherein a catheter is utilized including a body having a proximal end and a distal end. The distal end of the body comprises an arrangement of non-contact electrodes and a distal tip with a contact electrode. The non-contact electrodes are adapted for measuring far field electrical signals in the heart chamber, which allows determining electrical properties with a low spatial and temporal resolution only. The single contact electrode at the distal tip allows measuring the electrical properties of the heart chamber directly on the endocardial surface of the heart chamber, i.e. more accurately than by using the non-contact electrodes, but in order to acquire a map of the endocardial surface showing the electrical properties at different locations, the distal tip with the contact electrode has to be moved sequentially from location to location, which is time consuming.